update doc

README.md

@@ -104,7 +104,6 @@ Too many dependencies? Because OpenSCAD doesn't provide namespace management, I
 	- [sphere_spiral_extrude](https://openhome.cc/eGossip/OpenSCAD/lib-sphere_spiral_extrude.html)
 
 - Matrix
-	- [m_multiply](https://openhome.cc/eGossip/OpenSCAD/lib-m_multiply.html)
 	- [m_cumulate](https://openhome.cc/eGossip/OpenSCAD/lib-m_cumulate.html)	
 	- [m_translation](https://openhome.cc/eGossip/OpenSCAD/lib-m_translation.html)
 	- [m_rotation](https://openhome.cc/eGossip/OpenSCAD/lib-m_rotation.html)

docs/lib-m_mirror.md

@@ -1,23 +0,0 @@
-# m_mirror
-
-Generate a 4x4 transformation matrix which can pass into `multmatrix` to mirror the child element on a plane through the origin. 
-
-**Since:** 1.1
-
-## Parameters
-
-- `v` : The normal vector of a plane intersecting the origin through which to mirror the object.
-
-## Examples
-
-	include <m_mirror.scad>;
-
-	rotate([0, 0, 10]) 
-		cube([3, 2, 1]);
-		
-	multmatrix(m_mirror([1, 1, 0]))
-		rotate([0, 0, 10]) 
-			cube([3, 2, 1]);
-
-![m_mirror](images/lib-m_mirror-1.JPG)
-